Reaction characteristics of two-step methane reforming over a Cu-ferrite/Ce–ZrO2 medium

Methane was reformed over a Cu-ferrite/ZrO2 medium in a two-step process, consisting of a syn-gas production step and a water-splitting step. In the syn-gas production step, increase in Cu content in the CuxFe3−xO4/ZrO2 medium suppressed carbon deposition and enhanced the reaction rate for stoichiometries of x ≤ 0.7. In the water-splitting step, the addition of Cu promoted the gasification of the deposited carbon. Furthermore, the addition of Ce as a binder in the Cu0.7Fe2.3O4/Ce–ZrO2 medium also improved reactivity in the syn-gas production step and yielded the highest reactivity when the molar ratio of Ce/Zr was 3/1. As a result of the co-addition of Cu and Ce, the Cu0.7Fe2.3O4/Ce–ZrO2 medium showed high durability, with a constant evolution of the synthesis gas and hydrogen in ten repeated cycles. It is thus expected that the Cu-ferrite/Ce–ZrO2 medium is favourable for two-step methane reforming.